Inner door for railway boxcars



y 26, 1970 M. M. BAKKEN 3,513,901

INNER DOOR FOR RAILWAY BOXCARS Filed Sept. 16, 1968 2 Sheets-Sheet 1 y 6, 1970 M. M. BAKKEN 3,513,901

INNER DOOR FOR RAILWAY BOXCARS Filed Sept. 16, 1968 2 SheetsSheet 2 United States Patent 3,513,901 INNER DOOR FOR RAILWAY BOXCARS Maynard M. Bakken, P.O. Box 14, Chisholm Crescent NW., Calgary, Alberta, Canada Filed Sept. 16, 1968, Ser. No. 767,560 Claims priority, application Canada, Sept. 22, 1967, 750 Int. Cl. E06b 3/00 US. Cl. 160-368 11 Claims ABSTRACT OF THE DISCLOSURE An inner door for railway boxcars used for the carriage of grain and other finely divided bulk materials, consisting of a flexible supporting framework of rigid slats suspended inside the boxcar doorway, and a diaphragm adapted to cover the said framework on the inside of the doorway and thereby seal in the materials to be carried in the boxcar.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to improvements in inner doors for railway boxcars used for the carriage of grain or other finely divided bulk materials.

When finely divided or granular bulk materials, such as grain, fertilizer, or coal are carried in a railway boxcar, some means must be provided to tightly seal the doorway of the boxcar, as such materials tend to readily escape through the loosely fitting outer or storm doors. In order to prevent the escape of such materials, it has been known to employ a tightly fitting inner door. This invention relates to an improved type of inner door. An inner door for this purpose should be adapted to facilitate loading and unloading of the boxcar, should be economical, and should minimize damage to the boxcar occasioned by its installation and removal.

This invention is particularly directed to an inner door for boxcars used in the carriage of grain, and my disclosure will deal principally with the methods of its use in the carriage of grain and the advantages arising from such use. However, it will be apparent that the methods and advantages disclosed below are also applicable to the carriage of other finely divided bulk materials.

The characteristics of a suitable inner door for railway boxcars are governed by the nature of the materials to be transported, which is discussed above, and by the conditions at the points of loading and unloading of the boxcars.

In the carriage of grain, the loading point is usually a grain elevator operated by one man. Accordingly, the inner door should be one that can be easily, rapidly, and efiiciently installed by one man.

The unloading point is usually a grain terminal at a sea-port or a mill. Two methods of unloading grain from boxcars are commonly employed:

(1) Manually controlled power *shovels.-The inner door must be partially or completely removed so as to allow the entry into the boxcar of the work-men and their machines.

(2) Mechanical dumpers.-The outer or storm doors are opened manually, the inner door is broken open mechanically by an integral part of the dumper known as the door breaker, and the boxcar is mechanically unloaded by alternately tilting it in two directions to cause the grain to flow gravitationally through the opened doors. A mechanical dumper is capable of a certain number of car cycles per hour; in order for the dumper to work to capacity, it is imperative that the outer or storm doors be opened before the car is positioned on the 3,513 ,901 Patented May 26, 1970 dumper. It is therefore important that any inner door does not deflect sufficiently to touch and bind the outer doors, rendering manual opening difiicult.

Description of the [prior art SUMMARY OF THE INVENTION The description of my invention will show that it overcomes these difiicult-ies at the unloading point and that it is easily and efficien-tly installed. Moreover, it is economical having regard to the following cost factors:

(1) initial cost,

(2) durability,

(3) cost of repairs and replacement materials necessary to extend the life of the door,

(4) cost of repairing damage to the boxcar occasioned by installation and removal of the inner door,

(5) cost of distribution of doors from point of manufacture to point of installation, and cost of distributtion from point of removal to point of installation for reuse, and

(6) costs occasioned by leakage of :grain in transit.

My invention consists basically of suspension means in the upper part of a boxcar doorway, a supporting frame work of rigid slats which is freely suspended from the said means so that it hangs on the inside of the doorway, and an overlying diaphragm covering the framework and extending onto the floor of the boxcar, the diaphragm being lightly secured both to the inside of the boxcar doorway and to the floor of the boxcar, thereby providing an effective means for sealing in the finely divided bulk commodity to be loaded into the boxcar. The diaphragm is made of a material which may readily be cut or torn open, such as cardboard.

The advantages of my invention will become apparent from the following detailed description of a preferred embodiment thereof.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is an elevation of the boxcar door of this invention as applied to the inside of a boxcar doorway, with a portion of the diaphragm cut away to reveal the underlying structure.

FIG. 2 is a horizontal sectional view taken along line' 11 of FIG. 1.

FIG. 3 is a perspective view of a vertical section taken along line 2--2 of FIG. 1, showing the interior of the boxcar with a portion of the diaphragm cut away.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings for a more particular description of the preferred embodiment of my invention, a side wall of a railway boxcar is indicated at 1, and the floor of the boxcar at 2. The boxcar doorway 3 is provided with side frame members or nailing strips 4 and an upper frame member 5 which is the actual frame of the boxcar.

The installation in an empty boxcar of the inner door of the preferred embodiment of my invention is accomplished by first attaching a wooden suspension board 6 to the inner sides 4 of the doorway frame at a height equal to or above the level to which the boxcar will be loaded with grain or some other commodity. The suspension board 6 is attached to the doorway frame 4 by means of nails 7.

From the suspension board 6 is hung a framework 8 consisting of a plurality of slats 9 attached to two flexible vertical members 10. In the figures the vertical members 10 are chains, but they may also be cables, ropes, or any other flexible linear members of suitable size and strength. More than two such vertical members may, if necessary, be used. The chains 10 are attached to hooks 11 at one end for engagement with the suspension board 6. The framework 8 is preferably hung in such a manner that the chains 10 depend along the outer sides of the suspension board 6 and of the horizontal slats 9. This positioning of the chains prevents their interfering with the diaphragm 12.

It is obvious that the suspension means need not necessarily be a wooden board, but may also be a metal pipe or bar, or any other rigid member of suitable size and strength, and may be nailed to the doorway frame or attached by any other suitable means, such as metal brackets mounted on the doorway frame. The suspension member must be of suflicient strength to support the free-hanging framework of the door. Suspension for the door frame work can also be provided by means other than a suspension member, i.e. by holes in the doorway frame, or hooks or protrusions on the doorway frame. If desired, the framework may be permanently attached to the boxcar, as by bolting or welding the flexible vertical members directly to the boxcar doorway frame or ceiling.

The slats 9 are longer than the width of the doorway 3 and are of suflficient strength to withstand, without breakage or significant deflection, the pressure exerted by the commodity in a loaded boxcar. They may be made of metal, plastic or any other suitable material.

The pressure exerted on the door by a bulk material, such as grain, in the boxcar, reaches a maximum over the bottom one-third of the depth of the material. Moreover, the greatest inward pressure exerted by a mechanical door breaker occurs at the bottom part of the frame work 8. For these reasons it is preferable that the slats be most closely spaced near the bottom of the framework 8 with the spacing increasing toward the top of the framework, as is shown in FIGS. 1 and 3. This graduated spacing would obviously not be necessary if the slats were sufliciently strong or numerous, but it provides the most eflficient use of materials.

Since the framework 8 is hung so that the slats 9 are on the inside of the doorway, the slats are forced against the sides of the doorway by the pressure of the material in the boxcar when it is loaded, thereby preventing movement of the framework. It is evident that the dimensions of the framework 8 must be such that it effectively covers the doorway from the suspension board 6 to the floor.

When the framework 8 has been hung in position, the diaphragm 12 is placed over it on the inside of the boxcar doorway and lightly attached to the suspension board 6, the side frame members of the doorway 4 and the boxcar floor 2, thereby sealing the doorway and preventing the escape of any material from the boxcar when the latter is filled. Because the diaphragm itself bears no pressure, the degree of its attachment to the boxcar need only be minimalsuflicient only to hold the diaphragm in place until it is sealed by the pressure of the loaded commodity. In my preferred embodiment, I used staples 13 to attach the diaphragm.

The diaphragm 12 is made of cardboard or any other semi-rigid rupturable sheet material. In the figures it appears as a single sheet but it may be a composite made up of two or more sheets. It is wide enough to extend beyond the ends of the slats 9 for stapling to the doorway frame 4, as is best illustrated in FIG. 2. It is large enough. to cover the doorway from the suspension board 6 to the floor 2 and to provide a short extension 14 onto the floor l 2. It can be seen that installation and removal of my boxcar door will occasion only minimal damage to the structure of the boxcar because of the very light degree of attachment necessary. It can also be seen that the door of my invention may readily be installed by one man.

When the inner door has been installed, the boxcar is filled through the space between the suspension member 6 and the top of the doorway 5.

A boxcar employing my inner door may easily and conveniently be unloaded by either of the two common methods described above.

If unloading is to be carried out by manually operated power shovels, the diaphragm is slit between the slats near the floor allowing some of the material to flow out to relieve the pressure on the door. When the pressure has been relieved, the framework 8 may be forced inward, breaking the diaphragm away from the wall. The

framwork 8 is then unhooked, and the boxcar is entered and unloaded. Alternatively, the boxcar may be unloaded over the top of the free hanging door. The suspension member 6 is removed or the framework 8 unhooked and the slats drop as the pressure of the grain is released.

If unloading is to be carried out by mechanical dumpers, the boxcar is prepared for unloading by manually opening the outer or storm doors. The dumper door-breaker is then applied to the slats forcing the framework 8 a suflicient distance inward to rupture the diaphragm or break it away from the wall, allowing the loaded material to escape and relieve the pressure on the door. The door-breaker and free hanging framework 8 are then raised towards the ceiling in the usual manner, and unloading proceeds in the usual manner.

It can be seen that my inner door for boxcars achieves its desired objects of facility of installation and removal, and economy of operation. The only part of the door which regularly requires replacement or repair is the diaphragm. Damage occasioned to the boxcar is minimal. When not in use, the door may be folded into a compact unit for easy transportation, or storage within the boxcar. The door of my invention is simple and durable, and effectively seals grain or other bulk commodities in the boxcar.

I claim:

1. An inner door for a railway boxcar comprising:

(a) a flexible framework including a plurality of rigid slats of greater length than the width of the boxcar doorway, and of suflicient strength to withstand without breakage or significant deflection the pressure exerted by the commodity in the boxcar when loaded, the slats being held in a spaced relationship by attachment to flexible means extending transversely of said slats, the framework being freely suspended in the boxcar doorway so that the ends of the slats project beyond the sides of the doorway on the inside thereof, the said framework extending from the floor of the boxcar to a height equal to or above that to which the boxcar is to be loaded; and

(b) a diaphragm covering the suspended framework on the inside of the boxcar from the floor of the boxcar to a height equal to or above that to which the boxcar is to be loaded, extending beyond the sides of the boxcar doorway on the inside thereof, and extending a short distance onto the floor of the boxcar, the diaphragm being attached to the inside of the frame of the boxcar doorway and to the floor of the boxcar.

2. The invention defined in claim 1 wherein one end of the framework is permanently attached to the boxcar in the vicinity of the upper part of the boxcar doorway.

3. The invention defined in claim 1 wherein suspension means is provided in the upper part of the boxcar doorway and the flexible framework is freely suspended from the said means.

4. The invention defined in claim 3 wherein the suspension means is an elongated rigid member of somewhat greater length than the width of the boxcar doorway, said member being attached horizontally to the inside of the frame of the doorway at a height equal to or above that to which the boxcar is to be loaded.

5. The invention defined in claim 4 wherein said flexible means comprises at least two transverse flexible linear members, each of which is engaged with the elongated rigid member and wherein said slats are held in generally parallel spaced relationship.

6. The invention defined in claim 5 wherein the diaphragm is composed of one or more sheets of semi-rigid rupturable material and is of somewhat greater width than the length of the slats of the flexible framework 7. The invention defined in claim 6 wherein the elongated rigid member is a wooden board, each of the flexible linear members bears at one end a hook which is engaged with the wooden board, and the diaphragm comprises one or more sheets of cardboard, the diaphragm being stapled to the inside of the frame of the boxcar doorway and to the floor of the boxcar.

8. The invention defined in claim 7 wherein the spacing between adjacent slats of the flexible framework is least at the lower end of the framework and increases continuously toward the upper end thereof.

9. A method of sealing finely divided bulk materials in a railway boxcar by means of an inner door, comprising:

(a) providing suspension means in the upper part of the boxcar doorway at a height equal to or above that to which the boxcar is to be loaded;

(b) suspending from the suspension means a flexible framework of rigid slats of greater length than the width of the boxcar doorway and of suflicient strength to withstand breakage or significant deflection the pressure exerted by the commodity in a loaded boxcar so that the framework hangs on the inside of the boxcar doorway and the ends of the slats project beyond the sides of the doorway, the said framework extending from the said suspension means to the floor of the boxcar;

(c) holding the slats in spaced relationship by attaching the slats to flexible means extending transversely thereof;

(d) placing over the framework on the inside thereof a diaphrgam covering the framework to a height equal to or above that to which the boxcar is to be loaded, extending beyond the sides of the boxcar doorway on the inside thereof, and extending a short distance. onto the floor of the boxcar; and

(e) attaching the diaphragm to the inside of the frame of the boxcar doorway and to the floor of the boxcar.

10. The inveniton defined in claim 9' wherein:

(a) suspension means is provided by attaching an elongated rigid member of somewhat greater length than the width of the boxcar doorway in a horizontal position to the inside of the frame of the boxcar doorway at a height equal to or above that to which the boxcar is to be loaded;

(b) the step of holding the slats in a spaced relationship further comprising attaching the slats, in generally parallel spaced relationship, to at least two. transverse flexible linear members adapted at one end for engagement with the elongated rigid member; and

(c) the step of suspending comprising suspending the framework from the elongated rigid member.

11. The invention defined in claim 10 wherein:

(a) the step of holding the slats in generally parallel relationship comprises holding the slats so that the spacing between adjacent slats is least at the lowest end of the framework and increases continuously toward the upper end thereof; and wherein (b) the step of attaching the diaphragm to the inside of the doorway and to the floor of the boxcar is accomplished by stapling it thereto.

References Cited UNITED STATES PATENTS 2,381,15 8 8/1945 Green --166 2,596,413 5/1952 Kincaid 160-166 2,907,385 10/ 1959 Metcalfe.

3,177,927 4/ 1965 Starr.

3,291,195 12/1966 Blatt.

DAVID J. WILLIAMOWSKY, Primary Examiner P. C. KANNAN, Assistant Examiner 

